Another thing with those large rain gauges. I got the @#$% with measuring out the water in the large container into the 25 mm container 10 or more times to get a reading.. Then I noticed that the circumference of the cone and the large container are the same. So all I do is take the small container out, pour its water into the large container and then measure the depth of all the water in the large container with a ruler. Bingo.